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1/* SPDX-License-Identifier: GPL-2.0-or-later */2#ifndef _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H3#define _DRIVERS_VIRTIO_VIRTIO_PCI_COMMON_H4/*5 * Virtio PCI driver - APIs for common functionality for all device versions6 *7 * This module allows virtio devices to be used over a virtual PCI device.8 * This can be used with QEMU based VMMs like KVM or Xen.9 *10 * Copyright IBM Corp. 200711 * Copyright Red Hat, Inc. 201412 *13 * Authors:14 * Anthony Liguori <aliguori@us.ibm.com>15 * Rusty Russell <rusty@rustcorp.com.au>16 * Michael S. Tsirkin <mst@redhat.com>17 */18 19#include <linux/module.h>20#include <linux/list.h>21#include <linux/pci.h>22#include <linux/slab.h>23#include <linux/interrupt.h>24#include <linux/virtio.h>25#include <linux/virtio_config.h>26#include <linux/virtio_ring.h>27#include <linux/virtio_pci.h>28#include <linux/virtio_pci_legacy.h>29#include <linux/virtio_pci_modern.h>30#include <linux/highmem.h>31#include <linux/spinlock.h>32#include <linux/mutex.h>33 34struct virtio_pci_vq_info {35 /* the actual virtqueue */36 struct virtqueue *vq;37 38 /* the list node for the virtqueues or slow_virtqueues list */39 struct list_head node;40 41 /* MSI-X vector (or none) */42 unsigned int msix_vector;43};44 45struct virtio_pci_admin_vq {46 /* Virtqueue info associated with this admin queue. */47 struct virtio_pci_vq_info *info;48 /* Protects virtqueue access. */49 spinlock_t lock;50 u64 supported_cmds;51 /* Name of the admin queue: avq.$vq_index. */52 char name[10];53 u16 vq_index;54};55 56/* Our device structure */57struct virtio_pci_device {58 struct virtio_device vdev;59 struct pci_dev *pci_dev;60 union {61 struct virtio_pci_legacy_device ldev;62 struct virtio_pci_modern_device mdev;63 };64 bool is_legacy;65 66 /* Where to read and clear interrupt */67 u8 __iomem *isr;68 69 /* Lists of queues and potentially slow path queues70 * so we can dispatch IRQs.71 */72 spinlock_t lock;73 struct list_head virtqueues;74 struct list_head slow_virtqueues;75 76 /* Array of all virtqueues reported in the77 * PCI common config num_queues field78 */79 struct virtio_pci_vq_info **vqs;80 81 struct virtio_pci_admin_vq admin_vq;82 83 /* MSI-X support */84 int msix_enabled;85 int intx_enabled;86 cpumask_var_t *msix_affinity_masks;87 /* Name strings for interrupts. This size should be enough,88 * and I'm too lazy to allocate each name separately. */89 char (*msix_names)[256];90 /* Number of available vectors */91 unsigned int msix_vectors;92 /* Vectors allocated, excluding per-vq vectors if any */93 unsigned int msix_used_vectors;94 95 /* Whether we have vector per vq */96 bool per_vq_vectors;97 98 struct virtqueue *(*setup_vq)(struct virtio_pci_device *vp_dev,99 struct virtio_pci_vq_info *info,100 unsigned int idx,101 void (*callback)(struct virtqueue *vq),102 const char *name,103 bool ctx,104 u16 msix_vec);105 void (*del_vq)(struct virtio_pci_vq_info *info);106 107 u16 (*config_vector)(struct virtio_pci_device *vp_dev, u16 vector);108 int (*avq_index)(struct virtio_device *vdev, u16 *index, u16 *num);109};110 111/* Constants for MSI-X */112/* Use first vector for configuration changes, second and the rest for113 * virtqueues Thus, we need at least 2 vectors for MSI. */114enum {115 VP_MSIX_CONFIG_VECTOR = 0,116 VP_MSIX_VQ_VECTOR = 1,117};118 119/* Convert a generic virtio device to our structure */120static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)121{122 return container_of(vdev, struct virtio_pci_device, vdev);123}124 125/* wait for pending irq handlers */126void vp_synchronize_vectors(struct virtio_device *vdev);127/* the notify function used when creating a virt queue */128bool vp_notify(struct virtqueue *vq);129/* the config->del_vqs() implementation */130void vp_del_vqs(struct virtio_device *vdev);131/* the config->find_vqs() implementation */132int vp_find_vqs(struct virtio_device *vdev, unsigned int nvqs,133 struct virtqueue *vqs[], struct virtqueue_info vqs_info[],134 struct irq_affinity *desc);135const char *vp_bus_name(struct virtio_device *vdev);136 137/* Setup the affinity for a virtqueue:138 * - force the affinity for per vq vector139 * - OR over all affinities for shared MSI140 * - ignore the affinity request if we're using INTX141 */142int vp_set_vq_affinity(struct virtqueue *vq, const struct cpumask *cpu_mask);143 144const struct cpumask *vp_get_vq_affinity(struct virtio_device *vdev, int index);145 146#if IS_ENABLED(CONFIG_VIRTIO_PCI_LEGACY)147int virtio_pci_legacy_probe(struct virtio_pci_device *);148void virtio_pci_legacy_remove(struct virtio_pci_device *);149#else150static inline int virtio_pci_legacy_probe(struct virtio_pci_device *vp_dev)151{152 return -ENODEV;153}154static inline void virtio_pci_legacy_remove(struct virtio_pci_device *vp_dev)155{156}157#endif158int virtio_pci_modern_probe(struct virtio_pci_device *);159void virtio_pci_modern_remove(struct virtio_pci_device *);160 161struct virtio_device *virtio_pci_vf_get_pf_dev(struct pci_dev *pdev);162 163#define VIRTIO_LEGACY_ADMIN_CMD_BITMAP \164 (BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_WRITE) | \165 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_COMMON_CFG_READ) | \166 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_WRITE) | \167 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_DEV_CFG_READ) | \168 BIT_ULL(VIRTIO_ADMIN_CMD_LEGACY_NOTIFY_INFO))169 170/* Unlike modern drivers which support hardware virtio devices, legacy drivers171 * assume software-based devices: e.g. they don't use proper memory barriers172 * on ARM, use big endian on PPC, etc. X86 drivers are mostly ok though, more173 * or less by chance. For now, only support legacy IO on X86.174 */175#ifdef CONFIG_VIRTIO_PCI_ADMIN_LEGACY176#define VIRTIO_ADMIN_CMD_BITMAP VIRTIO_LEGACY_ADMIN_CMD_BITMAP177#else178#define VIRTIO_ADMIN_CMD_BITMAP 0179#endif180 181bool vp_is_avq(struct virtio_device *vdev, unsigned int index);182void vp_modern_avq_done(struct virtqueue *vq);183int vp_modern_admin_cmd_exec(struct virtio_device *vdev,184 struct virtio_admin_cmd *cmd);185 186#endif187